8wks in and I'm noticing my cm is dark brown when I wipe today, no other signs of blood tho?

No cramping/ pains and all my pregnancy symptoms are the same as usual. I took a pregnancy test to check I'm still producing hcg and it was an immediate clear positive as the dye ran up... but not a dye steeler as I was hoping with me being 8wks along. Booked in for a private scan tomorrow for reassurance but just wondered if anyone had any thoughts/ similar experiences?